Similar Datasets
Project description:The cnidarian model organism Hydra has long been studied for its remarkable ability to regenerate its head, which is controlled by a head organizer located near the hypostome. Cnidarians and bilaterians diverged about 600 millions years ago but the gene contents of species of both phyla are surprisingly similar despite divergent morphologies and functions. While little is known about the role of cis-regulatory elements in cnidarians, understanding gene regulatory mechanisms in cnidarians can potentially shed light on metazoan evolution. The canonical Wnt pathway plays a central role in head organizer function during regeneration and during bud formation, which is the asexual mode of reproduction in Hydra. However, it is unclear how shared the developmental programs of head organizer genesis are in budding and regeneration. Time-series analysis of gene expression changes during head regeneration and budding revealed a set of 298 differentially expressed genes during the 48-hour head regeneration and 72-hour budding time-courses. In order to understand the regulatory elements controlling hydra head regeneration, we first identified 27,137 open-chromatin elements that are open in one or more sections of organism. We used histone modification ChIP-seq to identify 9998 candidate proximal promoter and 3018 candidate enhancer-like regions respectively. We show that a subset of these regulatory elements is dynamically remodeled during head regeneration and identify a set of transcription factor motifs that are enriched in the enhancer regions activated during head regeneration. Our results show that Hydra displays complex gene regulatory structures of developmentally dynamic enhancers, which suggests that the evolution of complex developmental enhancers predates the split of cnidarians and bilaterians.
2019-12-31 | GSE127279 | GEO
Project description:The cnidarian model organism Hydra has long been studied for its remarkable ability to regenerate its head, which is controlled by a head organizer located near the hypostome. Cnidarians and bilaterians diverged about 600 millions years ago but the gene contents of species of both phyla are surprisingly similar despite divergent morphologies and functions. While little is known about the role of cis-regulatory elements in cnidarians, understanding gene regulatory mechanisms in cnidarians can potentially shed light on metazoan evolution. The canonical Wnt pathway plays a central role in head organizer function during regeneration and during bud formation, which is the asexual mode of reproduction in Hydra. However, it is unclear how shared the developmental programs of head organizer genesis are in budding and regeneration. Time-series analysis of gene expression changes during head regeneration and budding revealed a set of 298 differentially expressed genes during the 48-hour head regeneration and 72-hour budding time-courses. In order to understand the regulatory elements controlling hydra head regeneration, we first identified 27,137 open-chromatin elements that are open in one or more sections of organism. We used histone modification ChIP-seq to identify 9998 candidate proximal promoter and 3018 candidate enhancer-like regions respectively. We show that a subset of these regulatory elements is dynamically remodeled during head regeneration and identify a set of transcription factor motifs that are enriched in the enhancer regions activated during head regeneration. Our results show that Hydra displays complex gene regulatory structures of developmentally dynamic enhancers, which suggests that the evolution of complex developmental enhancers predates the split of cnidarians and bilaterians.
2019-12-31 | GSE127277 | GEO
Project description:The cnidarian model organism Hydra has long been studied for its remarkable ability to regenerate its head, which is controlled by a head organizer located near the hypostome. Cnidarians and bilaterians diverged about 600 millions years ago but the gene contents of species of both phyla are surprisingly similar despite divergent morphologies and functions. While little is known about the role of cis-regulatory elements in cnidarians, understanding gene regulatory mechanisms in cnidarians can potentially shed light on metazoan evolution. The canonical Wnt pathway plays a central role in head organizer function during regeneration and during bud formation, which is the asexual mode of reproduction in Hydra. However, it is unclear how shared the developmental programs of head organizer genesis are in budding and regeneration. Time-series analysis of gene expression changes during head regeneration and budding revealed a set of 298 differentially expressed genes during the 48-hour head regeneration and 72-hour budding time-courses. In order to understand the regulatory elements controlling hydra head regeneration, we first identified 27,137 open-chromatin elements that are open in one or more sections of organism. We used histone modification ChIP-seq to identify 9998 candidate proximal promoter and 3018 candidate enhancer-like regions respectively. We show that a subset of these regulatory elements is dynamically remodeled during head regeneration and identify a set of transcription factor motifs that are enriched in the enhancer regions activated during head regeneration. Our results show that Hydra displays complex gene regulatory structures of developmentally dynamic enhancers, which suggests that the evolution of complex developmental enhancers predates the split of cnidarians and bilaterians.
2019-12-31 | GSE127278 | GEO
Project description:Integrative analysis of Hydra head regeneration reveals activation of distal enhancer-like elements
| PRJNA524651 | ENA
Project description:Integrative analysis of Hydra head regeneration reveals activation of distal enhancer-like elements [RNA-seq]
| PRJNA524655 | ENA
Project description:Integrative analysis of Hydra head regeneration reveals activation of distal enhancer-like elements [ChIP-seq]
| PRJNA524656 | ENA
Project description:Integrative analysis of Hydra head regeneration reveals activation of distal enhancer-like elements [ATAC-seq]
| PRJNA524657 | ENA
Project description:BACKGROUND:Axis patterning during development is accompanied by large-scale gene expression changes. These are brought about by changes in the histone modifications leading to dynamic alterations in chromatin architecture. The cis regulatory DNA elements also play an important role towards modulating gene expression in a context-dependent manner. Hydra belongs to the phylum Cnidaria where the first asymmetry in the body plan was observed and the oral-aboral axis originated. Wnt signaling has been shown to determine the head organizer function in the basal metazoan Hydra. RESULTS:To gain insights into the evolution of cis regulatory elements and associated chromatin signatures, we ectopically activated the Wnt signaling pathway in Hydra and monitored the genome-wide alterations in key histone modifications. Motif analysis of putative intergenic enhancer elements from Hydra revealed the conservation of bilaterian cis regulatory elements that play critical roles in development. Differentially regulated enhancer elements were identified upon ectopic activation of Wnt signaling and found to regulate many head organizer specific genes. Enhancer activity of many of the identified cis regulatory elements was confirmed by luciferase reporter assay. Quantitative chromatin immunoprecipitation analysis upon activation of Wnt signaling further confirmed the enrichment of H3K27ac on the enhancer elements of Hv_Wnt5a, Hv_Wnt11 and head organizer genes Hv_Bra1, CnGsc and Hv_Pitx1. Additionally, perturbation of the putative H3K27me3 eraser activity using a specific inhibitor affected the ectopic activation of Wnt signaling indicating the importance of the dynamic changes in the H3K27 modifications towards regulation of the genes involved in the head organizer activity. CONCLUSIONS:The activation-associated histone marks H3K4me3, H3K27ac and H3K9ac mark chromatin in a similar manner as seen in bilaterians. We identified intergenic cis regulatory elements which harbor sites for key transcription factors involved in developmental processes. Differentially regulated enhancers exhibited motifs for many zinc-finger, T-box and ETS related TFs whose homologs have a head specific expression in Hydra and could be a part of the pioneer TF network in the patterning of the head. The ability to differentially modify the H3K27 residue is critical for the patterning of Hydra axis revealing a dynamic acetylation/methylation switch to regulate gene expression and chromatin architecture.
| S-EPMC7552563 | biostudies-literature
Project description:Hydra has long been studied for its remarkable ability to regenerate its head. Previous studies focusing on molecular mechanisms of axial patterning and head regeneration using a candidate gene approach have revealed a central role for the canonical Wnt pathway. We performed a global gene expression analysis during Hydra magnipapillata head regeneration using RNA-seq to identify additional genes that are transcriptionally regulated during the regeneration of the head organizer in hydra. Differential expression analysis revealed a set of 4,978 genes with significant changes during a 48-hour head regeneration time-course that includes many key genes in the Wnt, TGF-M-NM-2/BMP and MAP kinase pathways. We observed the differential regulation of several genes that are part of the epithelial-to-mesenchymal transition in bilaterians such as Snail. We assembled 806 novel putative lincRNAs with 176 of these are differentially expressed during the time course. We observed the coordinated transcriptional regulation of several factors that regulate the effective pool of free M-NM-2-catenin that together synergize to increase the amount of M-NM-2-catenin available for transcriptional regulation of downstream genes. The differential expression of Snail and some of its interacting regulators and downstream targets suggests that a partial-EMT-like response is involved in hydra head regeneration. This time-course is a valuable resource for the study of the transcriptional dynamics of head regeneration in hydra. mRNA profiling of regenerating head from 6 time points post bisection of Hydra head (H. magnipapillata), generated by deep sequencing, in duplicates, using Illumina HiSeq2500.
2014-12-13 | E-GEOD-64127 | biostudies-arrayexpress
Project description:Hydra has long been studied for its remarkable ability to regenerate its head. Previous studies focusing on molecular mechanisms of axial patterning and head regeneration using a candidate gene approach have revealed a central role for the canonical Wnt pathway. We performed a global gene expression analysis during Hydra magnipapillata head regeneration using RNA-seq to identify additional genes that are transcriptionally regulated during the regeneration of the head organizer in hydra. Differential expression analysis revealed a set of 4,978 genes with significant changes during a 48-hour head regeneration time-course that includes many key genes in the Wnt, TGF-β/BMP and MAP kinase pathways. We observed the differential regulation of several genes that are part of the epithelial-to-mesenchymal transition in bilaterians such as Snail. We assembled 806 novel putative lincRNAs with 176 of these are differentially expressed during the time course. We observed the coordinated transcriptional regulation of several factors that regulate the effective pool of free β-catenin that together synergize to increase the amount of β-catenin available for transcriptional regulation of downstream genes. The differential expression of Snail and some of its interacting regulators and downstream targets suggests that a partial-EMT-like response is involved in hydra head regeneration. This time-course is a valuable resource for the study of the transcriptional dynamics of head regeneration in hydra.
2014-12-13 | GSE64127 | GEO